In: Anatomy and Physiology
1). At the periphery each osteon is cement line, a narrow area of cement like ground substance composed primarily of GAGs.... The canaliculi of the osteon do not pass this cement line. Like the canaliculi the collagen fibres in the bone matrix interconnected from one lamella to another within an osteon but do not cross the cement line... This intertwining of collagen fibres within osteon increases the bone resistance to mechanical stress and probably explain why the cement line is weakest portion of osteons microstructure in bone......
2).
Compact bone, or cortical bone, mainly serves a mechanical function. This is the area of bone to which ligaments and tendons attach. It is thick and dense.
Trabecular bone, also known as cancellous bone or spongy bone, mainly serves a metabolic function. This type of bone is located between layers of compact bone and is thin porous. Location within the trabeculae is the bone marrow.
5). Isolated tibial fractures are caused predominantly by torsional forces, and most are localized in the distal third or at the junction of the middle and distal thirds of the tibia. The most common mechanism of torsion was lateral rotation of the body while the foot was in a fixed position on the ground......
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